1. Field of the Invention
This invention relates to foaming emulsions based on alkyl oligoglycosides, to a process for their production, in which a pre-emulsion is prepared from an oil phase and a polymer phase and a surfactant phase is stirred into the pre-emulsion thus formed, to shower baths containing these emulsions and to the use of the emulsions for the production of hair-care and body-care products.
2. Statement of Related Art
Alkyl oligoglycosides are nonionic surfactants which are distinguished not only by favorable foaming and cleaning power, but also and in particular by ready biodegradability and particularly advantageous dermatological compatibility. Accordingly, this class of surface-active compounds is acquiring increasing significance for the manufacture of cosmetic products. Relevant synoptic articles have been published, for example, by D. Balzer et al. in Tens. Surf. Det. 28, 419 (1991) and Seifen-Ole-Fette-Wachse 118, 894 (1992).
Alkyl oligoglycosides and, in particular, alkyl oligoglucosides are known in principle as ingredients of a number of cosmetic products.
Formulations containing sulfosuccinates in addition to short-chain alkyl oligoglucosides, for example for hair shampoos and shower baths, are disclosed in Riv. Ital. 56, 567 (1974).
Foaming detergent mixtures containing a number of anionic, nonionic and amphoteric surfactants in addition to alkyl oligoglucosides are known, for example, from EP-B-0 070 074, EP-B-0 070 075, EP-B-0 070 076 and EP-B-0 070 077 (Procter & Gamble).
In addition, mixtures of alkyl oligoglucosides with alkyl(ether) phosphates [1], cationic polymers [2], monoalkyl sulfosuccinates [3], silicone compounds [4] and sugar esters [5], which may be used for cosmetic purposes, are also known (for [1], see EP-A-0 324 451; for [2], see EP-A-0 337 354; for [3], see EP-A-0 358 216; for [4] see EP-A-0 398 117 and for [5] see EP-A-0 409 005, all Kao). DE-B-41 29 926 (Kao) relates to tinting shampoos which may contain sulfosuccinates, sarcosinates and amine oxides in addition to alkyl oligoglucosides.
EP-A-0 384 983 and EP-A-0 490 041 (Huls) describe shower baths and hair shampoos containing ether carboxylic acids and electrolyte salts or sulfate surfactants in addition to alkyl oligoglucosides. The use of mixtures containing alkyl oligoglucosides, polymers and salts as thickeners for surfactants in cosmetics is proposed in DE-A-41 14 141 (Huls).
DE-A-36 40 755 (Henkel) relates to aqueous, free-flowing pearlescent concentrates containing mixtures of alkyl oligoglucosides and polyethylene glycol esters or fatty acid alkanolamides. DE-A-40 33 928 (Henkel) describes oil-in-water emulsions containing oils, fatty acid partial glycerides and saturated alcohols in addition to alkyl oligoglucosides.
In addition, shampoos containing octyl decyl glucoside, collagen derivatives and polymers are known from an article by B. Brancq in Seifen-Ole-Fette-Wachse 118, 905 (1992). Finally, formulations of C.sub.8/10 alkyl glucoside and sulfosuccinates are disclosed in the same article.
However, there is still a growing need in the field of hair-care and body-care products for particularly mild formulations which combine aspects of cleaning and care with one another in addition to showing good dermatological compatibility. A typical example of such formulations are so-called "two-in-one" shower or foam baths which simultaneously cleanse and cream the skin.
Although products of the type in question are known in principle, they are often unsatisfactory from the point of view of practical application. The emulsions lack cosmetic elegance, i.e. they gel and are not readily absorbed by the skin and, instead of a creamy microfoam, they only form a coarse macrofoam. The production of stable emulsions of the type mentioned which do not separate in the event of prolonged storage has also proved to be difficult in the past and requires a complicated technique for homogenization.
Accordingly, the problem addressed by the present invention was to provide new foaming emulsions which would be free from the described disadvantages.